IBM deploys x64 battle waggon

When Intel was rolling its Nehalem-EX Xeon 7500 processors into position on the hills high above the x64 war last Spring, IBM kicked out two boxes and promised it had another one in the works.

In three weeks, the System x3690 X5 server - an armored personnel carrier compared to the System x3850 X5 tank and the HX5 blade attack copter - will take the field.

The System x3690 X5 uses IBM's own eX5 chipset, as the name suggests. So do the BladeCenter HX5 blade server (which supports two or four sockets) and the System x3850 X5, a four socket machine, which El Reg told you all about here.

Thanks for the memory

Both the BladeCenter HX5 and the x3850 X5 allow for a chassis equipped with only main memory to be linked through the eX5 chipset to allow for memory to be scaled up independently of processor sockets.

Each HX5 blade has 16 DDR3 memory slots and can have a Max5 memory extender with 24 additional memory slots, adding 192GB (using 8GB memory sticks) to the 128GB on the blade. The System x3850 has 64 memory slots, and the Max5 extender (which comes in a half-U form factor with 32 memory slots) can boost memory on this box by 50 per cent.

The System x3690 X5 server that begins shipping on August 23 supports the four-core, six-core, and eight core variants of the Xeon 7500s and their two-socket HPC brethren, the Xeon 6500s. You can get the lowdown on the Nehalem-EX processors here.

IBM is supporting all eight variants of the Nehalem-EX chips in the System x3690 X5, including the hottest 130 watt parts. The server has 32 memory slots, and with a special memory expansion card, customers can use very fat 16GB DDR3 memory sticks, boosting main memory up to 512GB inside of the chassis.

The memory cards used in the eX5 rack servers are based on Intel's scalable memory buffer architecture, which puts memory on daughter cards that slot into the system board. These cards have memory buffers to give them lots of bandwidth into the CPUs. IBM says that the System x3690 X5 design has four independent memory buses linking each socket to memory, giving 16GB/sec of memory bandwidth between the CPU and the buffered memory.

The Max5 memory expansion chassis for the x3690 X5 server has 32 memory slots, and that means in a 2.5U configuration, the System x3690 X5 server can deliver 1TB of main memory for two processor sockets, sporting 8, 12, or 16 cores. That is a heck of a lot of memory per core - exactly what customers who are looking to virtualize their servers and cut down on their footprints need.

The Max5 feature allows for memory scalability, but the FlexNode feature lets two x3690s to be glued together with a special connection cable that links both machines to the eX5 chipset, creating a four-socket symmetric multiprocessing (SMP) box that spans two 2U form factors. So in 5U of rack space, IBM can snap together a four-socket, 2TB behemoth.

IBM's System x3690 X5 Nehalem-EX workhorse

As you can see in the picture, the System x3690 X5 server has room for sixteen small form factor disk drives to be hot-plugged into the box (8TB max using 500GB disks). The server has four PCI-Express 2.0 slots (two x8 low-profile and two x8 standard slots), and up to four 675-watt power supplies.

A dual-port Gigabit Ethernet interface (from Broadcom) is on the system board and a dual-port 10 Gigabit Ethernet card with virtual fabric capabilities (from Emulex) is available. This latter adapter, which snaps onto the system board, has Fibre Channel over Ethernet (FCoE) capability, which IBM is in the process of certifying. IBM is also supporting 50GB micro-SATA flash disks in this server, which cost $999 a pop.

The Max5 memory extender is not supported with VMware's ESX Server 4.0 or ESXi 4.0 hypervisors, but the 4.1 release of the hypervisor, which was announced two weeks ago, does know about the Max5 memory extension used in the eX5 machines from Big Blue.

The base System x3690 comes with a single four-core E7520 processor, which spins at 1.86GHz, 8GB of memory, and no disk or operating system. This basic box costs $5,845.

With two of the eight-core X7550 processors, which clock at 2GHz, plus 16GB of memory, you're talking $13,475 in a base config. Beef that up to eight disk drives with RAID protection and 128GB of memory, then you are in for $30,812. ®